Device for decanting a liquid from hollow objects



H. LEMS April 5, 1960 DEVICE FOR DECANTING A LIQUID FROM HOLLOW OBJECTSFiled June 21. 1956 3 Sheets-Sheet l INVENTOR HENDRIK LEMS BY AGENTH.LEMS

DEVICE FOR DECANTING A LIQUID FROM HOLLOW OBJECTS Filed June 21, 1956 3Sheets-Sheet 2 INVENTOR HENDRIK LEM 5 AGENT A ril 5, 1960 I H. LEMSFiled June 21, 1956 DEVICE FOR DECANTING A LIQUID FROM HOLLOW OBJECTSFIG. 3

INVENTOR HENDRIK LEMS AGENT s Sheets-Sheet s Fflie ism P te 2,931,527DEVICE FOR DECANTING A LIQUID FROM HOLLOW OBJECTS Hendrik Lems,Eindhoven, Netherlands, assignor, by

mesne assignments, to North American Philips Company, Inc., New York,N.Y., a corporation of Delaware Application June 21, 1956, Serial No.592,814

3 Claims. (Cl. 214-318) the hollow object has introduced into it aliquid, which serves as a carrier for the chemicals for producing thecovering. layer. These chemicals may be contained in the liquid, forexample, as an emulsion or may be dissolved therein or may float as alayer on the liquid. The liquid and any excess chemicals must be removedfrom the hollow object, which is usually effected by decanting. Thedecanting process must take place very carefully, since during decantingeither the desired covering layer is applied to the wall of the object,or an existing covering layer, which has been formed, for example, bysettling down, must not be disturbed.

The abovementioned problem may occur, for example, in applying silvermirrors to Dewar vessels, in which the wall is provided with a thincovering layer before applying the metallic layer.

In electric discharge tubes also it may be desirable for the wall to beprovided with a certain covering layer. Thus, in iconoscopes, a layer ofsmall oxidized silver balls is frequently covered with a film of foilbefore the metallic layer is provided.

By way of example, reference may also be made to r the internal coatingof an object with a luminescent layer of organic material e.g. anitrocellulose solution.

For this purpose the cathode-ray tube is filled with liquid, for examplewater, whereafter a certain amount of a nitrocellulose solution ispoured onto the water, which layer floats on the water. vWhen the liquidis decanted, the hitrocellulose solution lays itself as a covering layeron the luminescent grains, while the water and the excess nitrocellulosesolution is decanted.

It is also possible to provide a film on the water level, which filmlays itself as a foil on the luminescent layer after the water has beendecanted. Said film may be obtained, for example, if a drop of zaponlacquer is poured onto the water level.

objects on an endless belt, the extremity of which runs 1 over a rollerand of which the parts moving forwards and backwards are located overone another. When the roller is passed, the objects are tipped. Thismethod has the disadvantage that the installation is voluminous anddifficult to make free from vibration. Besides, the tilting 2,931,527Patented Apr. 5, 1969 movement in this device is a uniform rotation andthis is frequently undesirable.

The object of the invention is to mitigate the abovementioneddisadvantages.

The device according to the invention is characterized in that itcomprises a turret, which can rotate about a vertical shaft and whichpossesses means for securing the hollow objects, which means arepivotally arranged with respect to the turret, so that each means,together with the hollow object secured thereto, can be tilted,resulting in liquid being decanted from the hollow object, the devicealso comprising control means which co-operate with the means forsecuring the objects in such manner that, during rotation of the turret,said means are tilted at a given position.

The devices for securing the hollow objects may be realised in differentways. It is possible, for example,

.to provide this device with clamps holding the object in position. Inone advantageous embodiment of the invention, each of the means forsecuring the hollow objects comprises a table having a cavity, to whicha vacuum line is connected, while at least the edge of the cavity isprovided with resilient material. The resilient material may be, forexample, rubber.

If each of the means for securing the hollow objects comprises a holder,then according to another advantageous embodiment of the invention, eachholder may be secured to the turret by means of two lugs and tiltoutwardly.

The control means may be realised in different ways. It is possible, forexample, to move the means for securing the objects with the aid of oilpressure or air pressure. In one advantageous embodiment of theinvention, the control means comprise a rail surrounding the frame ofthe turret, each of the means for securing the hollow objects having aroller co-operating with the rail. This construction affords theadvantage that another program for the machine is obtained by replacingthe rail by another. i

In another embodiment of the invention, it is desirable for thisconstruction that the centre of gravity of the holder and the objectplaced thereon should be located such that the holder has a tendency totilt outwards. Due to this construction, the holder always pushesagainst the rail, so that the path of the rail is followed accurately.

In another embodiment of the invention, each holder also possesses asecond roller, the two rollers being located on each side of the railand one roller being pushed against the rail due to the weight of theholderand the object placed thereon, whereas the other roller is pulledagainst the rail by means of a spring, so that an additional guaranteeexists that the path of the rail is followed accurately.

in another embodiment of the invention, the rail may be realized in asimple manner and preferably comprises a circular rod, of which not onlythe upper side, but during the tilting of the holders also the side maybe utilized as a running surface. It has been found that it isfrequently advantageous that the tilting movement is no uniformrotation. Such may especially be the case, if during the decanting ofliquid a covering layer is applied to the wall. In one embodiment of theinvention, the angular speed of the tilting movement is varied duringdecanting. In another embodiment, the angular speed of the tiltingmovement during the last portion thereof is greater than during thefirst portion of this movement.

If a covering layer is to be applied to the wall, the tilting movementespecially during the first portion thereof preferably takes place veryregularly and slowly. In one embodiment of the invention, the controlmeans for tilting the objects are so shaped that the angulardisplaceass-1,527

mentis at most 20 per minute during the first portion of the tiltingmovement.

The first portion of the tilting movement may last from about 2 to 3minutes, the covering layer during this period laying itself against theupper side of the wall. Itds now desirable that the movement isaccelerated (allowance having to be made for the viscosity of thecovering layer) so that it may be achieved that the layer acquires auniform thickness. During this period, an angular displacement of even60 per minute may occur. .At the end of this period, the object istilted to such an extent that the liquid is decanted from it.

In order that the invention may be readily carried into effect, it willnow be described, by way of example, with reference to the accompanyingdrawings, in which:

Fig. 1 is a diagrammatic perspective view of a device "according to theinvention;

Fig. 2 is a perspective view on an enlarged scale of a table, on which ahollow object may beplaced;

Fig. 3 shows an example of the curve, after which the tilting'movementof the hollow object may take 1 "place.

The device shown in Figs. 1 and 2 comprises a turret '1, which issecured to a frame (not shown) and which can rotate in a horizontalplane about a vertical shaft 2. Supports 3 have lugs 4 arranged on thisturret at different areas. Rotatably arranged between the lugs 4 areholders each having a cavity 6 with resilient material 7 at 'fthe edgeand an aperture 8 for a vacuum connection, which aperture is connectedvia a line 9 to a central vacuum line. The holders each have two guiderollers, viz an upper roller 10 and a lower roller 11. The 'upperroller10 is rigidly secured to the holder, whereas the lower roller 11 canrotate at point 12 and is pulled "upwards by means of 'a spring 13.

The frameis surrounded by a rail 14, which co-operates with therollers10 and 11 of the holders 5 and which controls the tilting movement ofthe holders during the fro'tationjof the turret. Since the centres ofgravity of holders 5 are located externally, the rollers 10 "always'urge against the upper sideof the rail, therein ,supported by thetension of the springs 13, which pull jthe lower rollers 11 upwards.Each holder also has a discharge trough 15 for any liquid which mayreach the j lholder. A plurality of hollow objects, for examplecathode-ray tubes '16, of which only a few are shown, flare placed onthe holders. The rail 14 near the portion .17Qis so shaped that theholders tilt at this area.

The device operates as follows: The hollow objects, for example,cathode-ray tubes, which are filled, for example, with water, are placedon the holders, a layer of nitrocellulose solution, for example,floatingon the water level. The objects are pushed against the holdersas a result of the subpressure prevailing in the cavities 6 of theholders 5. The turret rotates about the shaft 2, ;so that the holders,together with the cathode-ray tubes,

tilt near the portion 17 of the rail. v,

During the first portion of the movement the tilting movement takesplace substantially uniformly with a small angular displacement, untilthe layer of the nitrocellulose solution has partly laid itself againstthe screen Subsequently, the angular disof the cathode-ray tube.placement is increased, so that finally the liquid is decanted from thecathode-ray tube and may be collected in a container 18. Subsequently,the holder tilts back, whereafter the cathode-ray tube may be removed bylocal suppression of the vacuum of the holder.

Figure 3 shows, byway of example, a decanting curve,

which the angular displacement of the holder and the time are plotted onthe vertical axis and the horizontal axis, respectively.

v This curve shows that during the first minutes the object tilts with asubstantially constant angular speed, which is small and less than 20per minute, wherea fter the angular displacement increases to aconsiderable extent and may be even more than 60 per minute.

The device according to the invention, in addition to being simple ofconstruction and little subject to vibration, has the advantage thatdifferent processes may be carried out on the turret. For this purposecommands maybe given in a simple and known manner.

If the device is used for providing a luminescent screen in televisiontubes, then at one stage of the turret the tubes may be filled with aliquid in which luminescent material is suspended. During some stages,this luminescent material rnay settle down so as to form a coveringlayer on the base of the tube.

At a subsequent stage, the liquid may be acidified, whereafter anitrocellulose solution is poured onto the liquid. Finally, the liquidmay be decanted, during which process the nitrocellulose layer laysitself on the luminescent layer. As an alternative, it is possible that,at one stage of the decanting process, while the tube still has itsaperture directed downwards, water is sprayed into the tube to removeany available covering layer on parts of the wall, where this layer isnot wanted.

If a different program is desired for the tilting movement, the rail 14may be replaced by another rail. The portion 17 of the rail 14 is bentdownwards and inwards to permit the tilting of the holders 5. Duringtilting, the rollers 10 and 11 no longer run along the upper side of therail 14, but along the side thereof.

What is claimed is:

1. A device for decanting liquid from container-like objects initiallyin a substantially vertical position comprising a rotatable turret, aplurality of holders for said objects each having a recess and resilientmaterial lining at least on the edge of said recess, each of saidholders being provided with a funnel-shaped trough having an opening, avacuum line connected to said recess, each of said container-likeobjects being located in a recess and held therein by thesubpressure'created therein means pivotally mounting said holder's onsaid turret for tilting said objects at predetermined locations wherebyany liquid on said holders is discharged through the opening in each ofsaid funnel-shaped troughs, a receptacle for collecting said decantedliquid, and control means on said device which during rotation of saidturret controls the location and tilting rate of said holders.

2. A device for decanting liquid from container-like objects initiallyin a substantially vertical position eons prising a rotatable turret, aplurality of holders for said objects, means pivotally mounting saidholders on 'said turret for tilting said objects more than atpredetermined locations, a receptacle for collecting said decantedliquid, control means on said device which during rotation of saidturret controls the location and tilting rate of said holders, saidcontrol means including a rail hav ing a portion bent downwardly andinwardly and surrounding said turret, and each holder being providedwith 'two rollers located at opposite sides of said rail and coactingtherewith, one of said rollers being spring-urged into engagement withsaid rail.

3. A device for decanting liquid from container-like objects initiallyin a substantially vertical position comprising a rotatable turret, aplurality of holders for said objects, means pivotally mounting saidholders on said turret for tilting said objects more than 90 atpredetermined locations, a receptacle for collecting said decantedliquid, control means on said device which during rotation of saidturret controls the location and tilting rate of said holders, saidcontrol means including a rail havwing a portion bent downwardly andinwardly and surrounding said turret, and each holder being providedwith at least one roller bearing against the top surface of said railand that during the first portion of said tilting movement the angulardisplacement of said holder is at most'20 per minute.

'(Refeien'ces'on renewin page) References Cited in the file of thispatent UNITED STATES PATENTS Johnson June 4, 1940 8 Y W Smith -Q. July23, 1940 Gladefelter et al Mar. 20, 1945 Vredenburg Mar. 6, 1951 Paksweret a1 Sept. 1, 1953 Schweitzer Sept 8, 1953 Lindsay Dec. 6, 1955

